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Acta Cryst. (2007). E63, m1677    [ doi:10.1107/S1600536807024439 ]

Diaquabis(ethylenediamine-[kappa]2N,N')zinc(II) bis(4-aminonaphthalene-1-sulfonate) dihydrate

M.-T. Li, X.-C. Fu, X.-Y. Wang and C.-G. Wang

Abstract top

In the title compound, [Zn(C2H8N2)2(H2O)2](C10H8NO3S)2·2H2O, the ZnII cation lies on an inversion centre and has a distorted octahedral coordination geometry, defined by four N atoms from two ethylenediamine ligands and two water O atoms. In the crystal structure, pairs of 4-aminonaphthalene-1-sulfonate anions are connected via N-H...O hydrogen bonds to form centrosymmetric R22(16) rings. Cations, anions and water molecules are further connected by N-H...O, O-H...O and O-H...N hydrogen bonds and [pi]-[pi] stacking interactions [with a centroid-to-centroid distance of 3.5099 (13) Å] to form a three-dimensional network.

Comment top

Due to the weak coordination strength of sulfonate anions with transition metals, the sulfonates usually act as the counterbalance of the charge (Kosnic et al., 1992; Shubnell et al., 1994; Gunderman et al., 1997). Herein, we report the crystal structure of such a novel compound, [Cu(en)2(H2O)2](ans)2 2H2O, (I), (en = diethylenediamine; ans = 4-aminonaphthalene-1-sulfonate). The molecular structure of (I) is shown in Fig.1. The Zn atom lies on an inversion center and has has a distorted octahedral geometry, coordinated by four N atoms from two diethylenediamine ligands, which lie in the equatorial plane, and by two water O atoms occupying the axial sites. The average Zn—N bond length of 2.1278 (16) Å, is longer than the Zn—N bond distances in [Zn(en)2(H2O)2](sap)23H2O (sap = 2-sulfanilamidopyrimidine; Zn—N 1.996 (2)–2.016 (2) Å) (Isik et al., 2005). The Zn—O bond distance of 2.2386 (17) Å, is significantly shorter than the Zn—O distances in [Zn(en)2(H2O)2](sap)2 (Zn—O 2.49 (2) Å and 2.68 (2) Å)(Isik et al., 2005). The naphthalene ring is essentially planar (r.m.s. deviation 0.002 Å), with the greatest deviation from planarity being 0.0258 (18)Å for C6. The S and N atoms deviate by 0.1632 (5) Å and 0.0035 (19) Å from the naphthalene plane, respectively. As shown in Fig.2, an organic cation layer is linked to an inorganic anionic layer through a series of N—H···O, O—H···O and O—H···N hydrogen bonds, and adjacent 4-aminonaphthalene-1-sulfonate anions are antiparallel, showing significant π-π interactions interactions. The plane-to-plane distances and displacement angles of Cg1···Cg2i are 3.378, 3.367 Å and 1.04, 16.37 °, respectively [Cg1 and Cg2 are C3—C7/C12 and C7—C12 ring centroids; symmetry code: (i) 1 - x, 2 - y, -z]). These interactions together with the hydrogen bonds stabilize the crystal structure.

Related literature top

The isostructural NiII, CuII and CdII analogues have been reported previously (Li et al., 2005a,b, 2006).

For related literature, see: Gunderman et al. (1997); Işık et al. (2005); Kosnic et al. (1992); Shubnell et al. (1994).

Experimental top

Ethylenediamine (0.06 g, 1 mmol) was added to an aqueous solution (20 mL) of Zn(OAc)2˙2H2O(0.110 g, 0.5 mmol). After the mixture was stirred for 2 h at the room temperature, the solution was then treated with 4-aminonaphthalene-1-sulfonic acid sodium salt tetrahydrate (0.32 g, 1 mmol) in 10 ml e thanol. After filtration, the colorless solutions were allowed to stand at room temperature. The well shaped colorless block crystals of the title complex were obtained by slow evaporation of solvent about one week.

Refinement top

The water H atoms and amine H atoms were located in a difference Fourier map and refined with the restraints O—H = 0.75 (2)–0.87 (2) Å and N—H = 0.782 (19)–0.915 (2) Å, and Uiso(H) = 1.5Ueq(carrier). H atoms on C atoms were placed in geometrically idealized positions and refined in riding mode, with C—H = 0.93 or 0.97 Å and Uiso(H) = 1.2Ueq(C).

Computing details top

Data collection: SMART (Bruker, 2001); cell refinement: SAINT (Bruker, 2001); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXS97 (Sheldrick, 1997); molecular graphics: SHELXTL (Bruker, 2001); software used to prepare material for publication: SHELXTL.

Figures top
[Figure 1] Fig. 1. The molecular structure of (I), showing ellipsoids at the 50% probability level [symmetry code: -x, -y, 1 - z].
[Figure 2] Fig. 2. Part of the crystal structure of (I), with hydrogen bonds shown as dashed lines.
[Diaquabis(ethylenediamine-κ2N,N')zinc(II)] [bis(4-aminonaphthalene-1-sulfonate)] dihydrate top
Crystal data top
[Zn(C2H8N2)2(H2O)2](C10H8NO3S)2·2H2OF(000) = 736
Mr = 702.11Dx = 1.575 Mg m−3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 3865 reflections
a = 12.425 (3) Åθ = 2.7–28.1°
b = 9.6851 (19) ŵ = 1.04 mm−1
c = 12.305 (3) ÅT = 292 K
β = 90.50 (3)°Block, colourless
V = 1480.7 (5) Å30.46 × 0.36 × 0.20 mm
Z = 2
Data collection top
Bruker SMART CCD area-detector
diffractometer		3354 independent reflections
Radiation source: fine-focus sealed tube2729 reflections with I > 2σ(I)
graphiteRint = 0.073
φ and ω scansθmax = 27.5°, θmin = 1.6°
Absorption correction: multi-scan
(SADABS; Bruker, 2001)		h = −12→16
Tmin = 0.647, Tmax = 0.820k = −12→12
9734 measured reflectionsl = −10→15
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.038Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.086H atoms treated by a mixture of independent and constrained refinement
S = 0.98 w = 1/[σ2(Fo2) + (0.0458P)2]
where P = (Fo2 + 2Fc2)/3
3354 reflections(Δ/σ)max < 0.001
236 parametersΔρmax = 0.47 e Å−3
10 restraintsΔρmin = −0.66 e Å−3
Crystal data top
[Zn(C2H8N2)2(H2O)2](C10H8NO3S)2·2H2OV = 1480.7 (5) Å3
Mr = 702.11Z = 2
Monoclinic, P21/cMo Kα radiation
a = 12.425 (3) ŵ = 1.04 mm−1
b = 9.6851 (19) ÅT = 292 K
c = 12.305 (3) Å0.46 × 0.36 × 0.20 mm
β = 90.50 (3)°
Data collection top
Bruker SMART CCD area-detector
diffractometer		3354 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2001)		2729 reflections with I > 2σ(I)
Tmin = 0.647, Tmax = 0.820Rint = 0.073
9734 measured reflectionsθmax = 27.5°
Refinement top
R[F2 > 2σ(F2)] = 0.038H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.086Δρmax = 0.47 e Å−3
S = 0.98Δρmin = −0.66 e Å−3
3354 reflectionsAbsolute structure: ?
236 parametersFlack parameter: ?
10 restraintsRogers parameter: ?
Special details top

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes.

Refinement. Refinement of F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > σ(F2) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F2 are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
Zn10.00000.00000.50000.02820 (11)
N10.00131 (16)0.16231 (19)0.38096 (15)0.0372 (4)
N2−0.01612 (14)0.16750 (18)0.60803 (15)0.0338 (4)
O10.17965 (13)0.00886 (17)0.51362 (15)0.0394 (4)
C10.02957 (17)0.2888 (2)0.4403 (2)0.0461 (6)
H1C0.01340.36900.39590.055*
H1D0.10600.28940.45720.055*
C2−0.03471 (18)0.2943 (2)0.54452 (19)0.0466 (6)
H2C−0.01310.37420.58700.056*
H2D−0.11070.30320.52730.056*
C30.38445 (13)0.94913 (18)0.18557 (14)0.0241 (4)
C40.44306 (15)1.0471 (2)0.24009 (15)0.0296 (4)
H40.40951.10220.29160.036*
C50.55247 (15)1.06581 (19)0.21962 (16)0.0310 (4)
H50.59041.13370.25730.037*
C60.60475 (15)0.98605 (17)0.14515 (15)0.0266 (4)
C70.54778 (14)0.87878 (17)0.08887 (14)0.0235 (4)
C80.59937 (15)0.79072 (19)0.01412 (15)0.0303 (4)
H80.67270.80100.00200.036*
C90.54368 (16)0.6911 (2)−0.04046 (16)0.0354 (5)
H90.57880.6347−0.09000.043*
C100.43368 (16)0.67369 (19)−0.02191 (15)0.0337 (4)
H100.39620.6051−0.05910.040*
C110.38054 (14)0.75566 (17)0.04986 (14)0.0274 (4)
H110.30730.74260.06060.033*
C120.43560 (14)0.86090 (16)0.10847 (14)0.0228 (4)
N30.71563 (14)1.00495 (19)0.12848 (16)0.0339 (4)
O20.21294 (11)0.80591 (14)0.23913 (12)0.0429 (4)
O30.19412 (12)0.98569 (15)0.10337 (13)0.0431 (4)
O40.22193 (11)1.04667 (15)0.29095 (12)0.0408 (4)
O50.20692 (14)0.1749 (2)0.70145 (14)0.0477 (4)
S10.24345 (4)0.94473 (5)0.20564 (4)0.02944 (13)
H1E0.2027 (19)0.060 (2)0.558 (2)0.056 (9)*
H1F0.206 (2)0.023 (3)0.4602 (19)0.055 (9)*
H3A0.7328 (17)1.075 (2)0.1555 (19)0.045 (7)*
H3B0.7366 (17)0.9997 (19)0.0642 (16)0.030 (6)*
H5A0.215 (2)0.250 (2)0.720 (2)0.077 (11)*
H5B0.226 (2)0.124 (3)0.757 (2)0.067 (9)*
H2A−0.0723 (18)0.151 (2)0.6477 (19)0.062 (8)*
H1A−0.0590 (15)0.169 (2)0.3507 (18)0.048 (7)*
H1B0.0491 (19)0.146 (3)0.332 (2)0.072 (9)*
H2B0.0438 (16)0.175 (2)0.6514 (18)0.049 (7)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Zn10.03346 (19)0.02544 (17)0.02576 (18)0.00102 (12)0.00379 (13)0.00048 (12)
N10.0362 (11)0.0407 (10)0.0347 (10)0.0026 (8)0.0058 (9)0.0084 (8)
N20.0300 (9)0.0361 (9)0.0354 (10)0.0002 (7)0.0058 (8)−0.0064 (8)
O10.0314 (8)0.0494 (10)0.0373 (9)−0.0016 (7)0.0041 (7)−0.0020 (8)
C10.0479 (13)0.0299 (10)0.0605 (15)−0.0024 (9)0.0058 (11)0.0109 (10)
C20.0516 (13)0.0294 (10)0.0589 (15)0.0065 (10)0.0076 (12)−0.0037 (10)
C30.0252 (9)0.0256 (8)0.0215 (9)−0.0002 (7)0.0032 (7)0.0040 (7)
C40.0349 (10)0.0307 (9)0.0233 (9)0.0012 (8)0.0042 (8)−0.0034 (8)
C50.0355 (10)0.0289 (9)0.0284 (10)−0.0056 (8)−0.0025 (8)−0.0042 (8)
C60.0270 (9)0.0283 (9)0.0244 (9)−0.0026 (7)−0.0012 (8)0.0067 (7)
C70.0272 (9)0.0231 (8)0.0203 (9)0.0014 (7)0.0011 (7)0.0045 (7)
C80.0297 (10)0.0325 (10)0.0288 (10)0.0050 (8)0.0061 (8)0.0029 (8)
C90.0432 (11)0.0315 (10)0.0317 (11)0.0056 (9)0.0081 (9)−0.0054 (8)
C100.0443 (12)0.0267 (9)0.0301 (11)−0.0049 (8)0.0004 (9)−0.0042 (8)
C110.0284 (9)0.0273 (9)0.0267 (10)−0.0034 (7)0.0010 (8)0.0013 (8)
C120.0278 (9)0.0221 (8)0.0186 (8)0.0007 (7)0.0026 (7)0.0034 (7)
N30.0279 (9)0.0405 (10)0.0332 (10)−0.0067 (7)0.0001 (8)0.0006 (8)
O20.0391 (8)0.0380 (8)0.0518 (10)−0.0064 (6)0.0161 (7)0.0035 (7)
O30.0302 (8)0.0623 (10)0.0370 (9)0.0054 (6)0.0007 (7)0.0058 (7)
O40.0390 (8)0.0435 (8)0.0400 (9)0.0044 (7)0.0145 (7)−0.0087 (7)
O50.0522 (10)0.0440 (10)0.0466 (10)−0.0010 (8)−0.0133 (8)0.0002 (8)
S10.0265 (2)0.0334 (3)0.0286 (3)0.00020 (19)0.00845 (19)−0.0001 (2)
Geometric parameters (Å, °) top
Zn1—N22.1080 (17)C4—H40.9300
Zn1—N2i2.1080 (17)C5—C61.367 (3)
Zn1—N1i2.1488 (18)C5—H50.9300
Zn1—N12.1488 (18)C6—N31.407 (3)
Zn1—O1i2.2386 (17)C6—C71.432 (2)
Zn1—O12.2386 (17)C7—C81.412 (2)
N1—C11.468 (3)C7—C121.427 (2)
N1—H1A0.836 (18)C8—C91.361 (3)
N1—H1B0.86 (2)C8—H80.9300
N2—C21.473 (3)C9—C101.398 (3)
N2—H2A0.87 (2)C9—H90.9300
N2—H2B0.915 (18)C10—C111.362 (2)
O1—H1E0.79 (2)C10—H100.9300
O1—H1F0.75 (2)C11—C121.421 (2)
C1—C21.517 (3)C11—H110.9300
C1—H1C0.9700N3—H3A0.782 (19)
C1—H1D0.9700N3—H3B0.836 (19)
C2—H2C0.9700O2—S11.4573 (15)
C2—H2D0.9700O3—S11.4504 (16)
C3—C41.369 (3)O4—S11.4674 (15)
C3—C121.430 (2)O5—H5A0.77 (2)
C3—S11.7719 (17)O5—H5B0.87 (2)
C4—C51.397 (3)
N2—Zn1—N2i180.0H2C—C2—H2D108.2
N2—Zn1—N1i97.57 (8)C4—C3—C12120.14 (16)
N2i—Zn1—N1i82.43 (8)C4—C3—S1118.09 (14)
N2—Zn1—N182.43 (8)C12—C3—S1121.59 (13)
N2i—Zn1—N197.57 (8)C3—C4—C5121.07 (17)
N1i—Zn1—N1180.0C3—C4—H4119.5
N2—Zn1—O1i88.66 (7)C5—C4—H4119.5
N2i—Zn1—O1i91.34 (7)C6—C5—C4121.12 (17)
N1i—Zn1—O1i90.55 (7)C6—C5—H5119.4
N1—Zn1—O1i89.45 (7)C4—C5—H5119.4
N2—Zn1—O191.34 (7)C5—C6—N3119.74 (17)
N2i—Zn1—O188.66 (7)C5—C6—C7119.88 (17)
N1i—Zn1—O189.45 (7)N3—C6—C7120.29 (17)
N1—Zn1—O190.55 (7)C8—C7—C12119.09 (16)
O1i—Zn1—O1180.0C8—C7—C6121.85 (16)
C1—N1—Zn1105.95 (13)C12—C7—C6119.05 (16)
C1—N1—H1A111.5 (16)C9—C8—C7121.18 (17)
Zn1—N1—H1A110.4 (16)C9—C8—H8119.4
C1—N1—H1B109.7 (17)C7—C8—H8119.4
Zn1—N1—H1B110.5 (17)C8—C9—C10119.90 (17)
H1A—N1—H1B109 (2)C8—C9—H9120.0
C2—N2—Zn1108.81 (13)C10—C9—H9120.0
C2—N2—H2A109.1 (16)C11—C10—C9121.03 (17)
Zn1—N2—H2A107.2 (16)C11—C10—H10119.5
C2—N2—H2B111.5 (15)C9—C10—H10119.5
Zn1—N2—H2B110.3 (15)C10—C11—C12120.88 (16)
H2A—N2—H2B110 (2)C10—C11—H11119.6
Zn1—O1—H1E115.4 (18)C12—C11—H11119.6
Zn1—O1—H1F113 (2)C11—C12—C7117.90 (15)
H1E—O1—H1F110 (3)C11—C12—C3123.41 (16)
N1—C1—C2108.92 (17)C7—C12—C3118.69 (15)
N1—C1—H1C109.9C6—N3—H3A108.4 (17)
C2—C1—H1C109.9C6—N3—H3B116.3 (15)
N1—C1—H1D109.9H3A—N3—H3B112 (2)
C2—C1—H1D109.9H5A—O5—H5B106 (3)
H1C—C1—H1D108.3O3—S1—O2112.87 (9)
N2—C2—C1109.75 (16)O3—S1—O4111.00 (9)
N2—C2—H2C109.7O2—S1—O4111.66 (9)
C1—C2—H2C109.7O3—S1—C3106.46 (9)
N2—C2—H2D109.7O2—S1—C3108.76 (8)
C1—C2—H2D109.7O4—S1—C3105.67 (9)
N2—Zn1—N1—C119.84 (14)C6—C7—C8—C9−178.60 (17)
N2i—Zn1—N1—C1−160.16 (14)C7—C8—C9—C10−0.7 (3)
O1i—Zn1—N1—C1108.55 (14)C8—C9—C10—C110.4 (3)
O1—Zn1—N1—C1−71.45 (14)C9—C10—C11—C12−0.3 (3)
N1i—Zn1—N2—C2−171.14 (14)C10—C11—C12—C70.7 (3)
N1—Zn1—N2—C28.86 (14)C10—C11—C12—C3−179.36 (17)
O1i—Zn1—N2—C2−80.76 (14)C8—C7—C12—C11−1.0 (2)
O1—Zn1—N2—C299.24 (14)C6—C7—C12—C11178.68 (15)
Zn1—N1—C1—C2−44.7 (2)C8—C7—C12—C3179.03 (16)
Zn1—N2—C2—C1−35.8 (2)C6—C7—C12—C3−1.3 (2)
N1—C1—C2—N255.4 (3)C4—C3—C12—C11179.11 (17)
C12—C3—C4—C51.9 (3)S1—C3—C12—C11−5.9 (2)
S1—C3—C4—C5−173.30 (14)C4—C3—C12—C7−0.9 (3)
C3—C4—C5—C6−0.6 (3)S1—C3—C12—C7174.10 (12)
C4—C5—C6—N3−178.31 (17)C4—C3—S1—O3112.32 (16)
C4—C5—C6—C7−1.7 (3)C12—C3—S1—O3−62.78 (16)
C5—C6—C7—C8−177.73 (17)C4—C3—S1—O2−125.78 (16)
N3—C6—C7—C8−1.2 (3)C12—C3—S1—O259.12 (16)
C5—C6—C7—C122.6 (2)C4—C3—S1—O4−5.78 (17)
N3—C6—C7—C12179.19 (16)C12—C3—S1—O4179.12 (14)
C12—C7—C8—C91.1 (3)
Symmetry codes: (i) −x, −y, −z+1.
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
N1—H1B···O4ii0.86 (2)2.41 (2)3.170 (2)147 (2)
N1—H1A···O2iii0.84 (2)2.57 (2)3.337 (3)153 (2)
N2—H2A···O2iv0.87 (2)2.28 (2)3.109 (2)159 (2)
N2—H2B···O50.92 (2)2.11 (2)2.992 (3)161 (2)
N3—H3A···O2v0.78 (2)2.67 (2)3.451 (2)176 (2)
N3—H3B···O3vi0.84 (2)2.25 (2)3.076 (3)172 (2)
O1—H1E···O50.79 (2)2.08 (2)2.834 (3)158 (2)
O5—H5B···N3vii0.87 (2)2.02 (2)2.882 (3)173 (3)
O5—H5A···O4viii0.77 (2)2.15 (2)2.918 (3)172 (3)
O1—H1F···O4ii0.75 (2)2.11 (2)2.818 (2)159 (3)
Symmetry codes: (ii) x, y−1, z; (iii) −x, y−1/2, −z+1/2; (iv) −x, −y+1, −z+1; (v) −x+1, y+1/2, −z+1/2; (vi) −x+1, −y+2, −z; (vii) −x+1, −y+1, −z+1; (viii) x, −y+3/2, z+1/2.
Table 1
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
N1—H1B···O4i0.86 (2)2.41 (2)3.170 (2)147 (2)
N1—H1A···O2ii0.84 (2)2.57 (2)3.337 (3)153 (2)
N2—H2A···O2iii0.87 (2)2.28 (2)3.109 (2)159 (2)
N2—H2B···O50.92 (2)2.11 (2)2.992 (3)161 (2)
N3—H3A···O2iv0.78 (2)2.67 (2)3.451 (2)176 (2)
N3—H3B···O3v0.84 (2)2.25 (2)3.076 (3)172 (2)
O1—H1E···O50.79 (2)2.08 (2)2.834 (3)158 (2)
O5—H5B···N3vi0.87 (2)2.02 (2)2.882 (3)173 (3)
O5—H5A···O4vii0.77 (2)2.15 (2)2.918 (3)172 (3)
O1—H1F···O4i0.75 (2)2.11 (2)2.818 (2)159 (3)
Symmetry codes: (i) x, y−1, z; (ii) −x, y−1/2, −z+1/2; (iii) −x, −y+1, −z+1; (iv) −x+1, y+1/2, −z+1/2; (v) −x+1, −y+2, −z; (vi) −x+1, −y+1, −z+1; (vii) x, −y+3/2, z+1/2.
Acknowledgements top

This work was supported by the Hubei Key Laboratory of Novel Chemical Reactions and Green Chemical Technology (grant No. RCT2004011).

references
References top

Bruker (2001). SHELXTL (Version 6.10), SMART (Version?), SAINT (Version?) and SADABS (Version 6.10). Bruker AXS Inc., Madison, Wisconsin, USA.

Gunderman, B. J., Kabell, I. D., Squattrio, P. J. & Dubey, S. N. (1997). Inorg. Chim. Acta, 258, 237–246.

Işık, S., Köysal, Y., Yavuz, M., Heren, Z. & Vurucu, L. (2005). Acta Cryst. E61, m2066–m2068.

Kosnic, E. J., Lynn McClymont, E., Hodder, R. A. & Squattrio, P. J. (1992). Inorg. Chim. Acta, 201, 143–151.

Li, M.-T., Wang, C.-G. & Fu, X.-C. (2006). Acta Cryst. C62, m434–m436.

Li, M.-T., Wang, C.-G., Wu, Y. & Fu, X.-C. (2005a). Acta Cryst. E61, m1613–m1615.

Li, M.-T., Wang, C.-G., Wu, Y. & Fu, X.-C. (2005b). Acta Cryst. E61, m1660–m1661.

Sheldrick, G. M. (1997). SHELXS97 and SHELXL97. University of Göttingen, Germany.

Shubnell, A. J., Kosnic, E. J. & Squattrio, P. J. (1994). Inorg. Chim. Acta, 216, 101–112.